This invention relates to a tracheal device which permits a patient to breath after a tracheotomy, and in particular, to a stoma stent with an integrated speech flap valve.
A tracheotomy is a surgical operation in which an incision, or opening, is cut through the front of the neck and into the trachea, or windpipe. A tracheotomy creates an alternate passage to the lungs for air that cannot flow from the nose and mouth through the trachea because of an obstruction. Obstructions may occur when a foreign body lodges in the larynx, or voice box, above the trachea; as a result of swelling or spasm of the larynx or vocal cords; or from infection and swelling of the epiglottis, the thin flap of cartilage covering that keeps food and liquid out of the trachea.
After a patient has undergone a tracheotomy, he is often provided with a tubular prosthesis, e.g., a short stationary tube, including air channel means between the trachea and the outside ambient air. A tracheotomy that includes the insertion of a tubular prosthesis into the trachea is called a tracheostomy. The purpose of a tracheostomy is to keep the airway from closing prematurely and to enable the physician to take further measures, if necessary, to ensure that the patient has a patent airway. The prosthesis is held in place in the stoma so that it may be used for long time periods, maintaining patentcy of the tracheostomy. Such prosthesis are known as stoma stents.
A tracheostomy prevents patients from using their vocal cords. Once the reason for having a tracheostomy has ended, the tracheostomy is closed and patients are able to breathe and speak normally. However, in some situations, a tracheostomy must remain in place for a period of time, often lengthy. This presents a particular physiological problem associated with prior art stents in that a patient with an open stent cannot use his vocal cords to speak.
Human speech is enabled by the passage of expired air from the lungs up though the trachea, passing through the laryngeal cavity and exhaled through the mouth. The laryngeal cavity contains a plurality of adjustable-tensioned mucous membranes, or vocal cords, stretched across the cavity. During such exhalation, these membranes are cause to vibrate and produce audible sounds by a flow of expired air, and differences in pitch are achieved by muscles which adjust the tension of these vibratory membranes.
With some stents one-way speech valves are offered as an accessory to the device. The valves close during exhalation thereby forcing air through the laryngeal cavity out through the mouth. During inhalation, the valves open bringing air in through the stent. These valves are designed to allow a patient to speak without physically occluding the stoma opening. With some prior art stents one-way valves are inserted into the stent. While these work, they also reduce air flow. Other types of valves are fitted over the stent and extend well beyond the stoma site. The added weight may require the stent to be tied in place.